In wireless communication systems, user devices equipped with multiple antennas are able to perform different diversity combining techniques to improve receiver performance. For example, receive beamforming traditionally uses downlink (DL) pilot measurements for obtaining DL channel information. This channel information can be used for calculating the antenna weights i.e. the receive filter. With receive filter usage, improvement can be achieved in user experienced signal-to-interference-plus-noise-ratio (SINR). Therefore, higher modulation and coding schemes (MCSs) can be used to increase throughputs.
In Long Term Evolution (LTE) systems, downlink reference signals, i.e. pilot symbols, can be measured for obtaining channel information. Downlink reference signals occupy time/frequency resource elements, which could also be used for data transmission. Hence, DL reference signals cause overhead and reduce the overall system capacity. Further, DL transmissions from other base stations can interfere with each other i.e. pilot pollution. Receive filters are typically sensitive to polluted reference signals due to the degraded channel estimation accuracy. On the other hand, if pollution is decreased by decreasing reference signal resource reuse, then overhead caused by reference signals will increase. If more physical resources are allocated for reference signaling, there are less physical resources for data transmission. It would be advantageous to use location measurements from uplink (UL) reference signals in receive beamforming and future standards.
Accordingly, it would be desirable to provide network aided beamforming that addresses at least some of the problems identified above.